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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 22 |
| 3 | 222 |
| 4 | 4444 |
| 5 | 88888 |
| 6 | 222222 |
| 7 | 18888888 |
| 8 | 1455555555 |
| 9 | 13888888888 |
| 10 | 54444444444 |
| 11 | 4788888888888 |
| 12 | 336888888888888 |
| 13 | 4011111111111111 |
| 14 | 8022222222222222 |
| 15 | 2769888888888888888 |
| 16 | 269454444444444444444 |
| 17 | 2375988888888888888888 |
| 18 | 138816111111111111111111 |
| 19 | 277632222222222222222222 |
[2,22,222,4444,88888,222222,18888888,1455555555, 13888888888,54444444444,4788888888888, 336888888888888,4011111111111111,8022222222222222, 2769888888888888888,269454444444444444444, 2375988888888888888888,138816111111111111111111, 277632222222222222222222] |